The present invention relates to an optical disk face discriminating system for discriminating which one of a recording face and a label face of an optical disk is set to oppose to a pickup, and an optical disk drive for forming an image on the label face.
The data recording onto the optical disk such as CD-R (Compact Disc-Recordable), CD-RW (Compact Disc-Rewritable), or the like is executed by irradiating a laser beam onto the recording face by the pickup. Therefore, a process of discriminating whether or not the optical disk is set in such a situation that the recording face opposes to the pickup is carried out before the data recording.
In this case, there is the technology to discriminate the type of disk such as a CD system, a DVD (Digital Versatile Disk) system, or the like simultaneously with such discriminating process (see Patent JP-A-2002-230793, for example).
Meanwhile, the inventors of this application have proposed the technology of providing the discolored layer, which is discolored by the heat or light, on the label face formed on the opposite side to the recording face integrally with the optical disk, and then forming an image, which is used to discriminate the data recorded on the recording face, on the label face by irradiating the laser beam onto the discolored layer to discolor it. In this case, this technology is not disclosed at the filing time of this application yet and does not constitute a prior art.
However, if the label face having the discolored layer thereon is discriminated, first it is discriminated resultantly that the recording face is not set to oppose to the pickup. However, according to such discriminated result, it is impossible to distinguish a situation in which the label face is set truly to oppose to the pickup from a situation in which, though simply the recording face is opposed to the pickup, the dust, the scratch, or the like on such recording face is incorrectly discriminated as the discolored layer.
Here, based on such a discriminated result that the recording face is not set to oppose to the pickup, if it is decided indirectly that the label face is opposed to the pickup, the laser beam is irradiated in error onto the recording face side, although the user intends to irradiate the laser beam onto the discolored layer so as to form the image. As a result, in the case that the data have already recorded on the recording face, there is such a disadvantage that the recorded data (pit) may be destroyed if the laser beam is irradiated again onto the recording face.
Therefore, in the case that the optical disk on the recording face of which the data are to be recorded and on the label face of which the image is to be formed respectively is employed, the technology of not only discriminating merely whether or not the recording face is opposed to the pickup but also discriminating directly whether or not the label face is opposed to the pickup is requested.